It's unclear if any of the affected models are sold in the US, but the company did say that some overseas vehicles will be affected by this latest development.

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Back in the spring, Mitsubishi admitted to using some less-than-correct tactics when calculating the fuel economy of four of its Japanese market vehicles, all of which were super-small "kei" cars. Now, it appears that issue extends beyond those four vehicles, and beyond the kei car segment entirely.

The Japanese transport ministry announced that its investigation into Mitsubishi's practices uncovered eight additional vehicles with misreported fuel economy numbers, including the Outlander SUV, Reuters reports. The ministry's tests found that some vehicles had mileage nearly 10 percent lower than was stated in marketing materials.

The automaker will stop selling those eight vehicles while it corrects its literature. Unlike before, this may also affect overseas vehicles, but it's unclear if that includes the United States. Mitsubishi's issue with fuel economy relates to how it performed the "coast down" test, which is part of the calculation used to determine fuel economy. It used this unapproved method for nearly 25 years.

Mitsubishi is Japan's sixth largest automaker, and its books have not reacted well to the fuel economy scandal. Money troubles caused the company to reach out to Nissan, which now owns a controlling stake in the company.

Mitsubishi has promised that it will change its ways, as an investigation into why this happened determined that the company was rather lax about compliance. The automaker also said that it would compensate Japanese owners affected by this misreporting.